That is a sokkia cable, I doubt if it would fit anything else. the modern sokkia cable looks the same. the SMI module I think went in the 41 separate, and the device added memory and the interface to plug the 9 pin RS232 cable to the instrument. I don't think this would be usable for anything other than a sokkia total station, unless you wanted to buy a different cable. I've used this way back but have forgot all the details of its use.

TW:
If you ask the seller and get the cable number i might be able to tell you what instrument it is for. The number will look something like: Cxxx001A. Even then, we may not know all the ones it will work with. I remember some topcon and leitz being able to share cables too.
The unit you may bid on is the battery and RAM case. the 41 could and did contain more modules. the TDS had surveying and plotter modules. The road stake / instrument modules each contained a different alignment /offset & random points routine with slope staking.... along with capabilities for a few instruments per ROM. I know TDS would do several instruments each of Nikon, Topcon, Kern, Lietz and Pentax. I believe they would also do Wild. Strangely; I never saw a ROM for the HP 3810B or 3820. I remember one Geodometer that would record only point number, descriptor and (senior moment here) either distance or maybe angle only, but not both. Probably distance.

These ROMs told the unit in the auction what code to use for the gun it was hooked up to. So to answer your question: yes it will, but:
the pinout of the plug will be proprietary, the plug will be rare, you'll have to tell it how to talk with whatever you want to talk with unless you have the right ROM, and one mistake and you'll blow it up. Otherwise, it's a fine play Mrs Lincoln.

I liked these and used them. They were just short of magic when they came out. I just preferred D'Zign Software in operation on the 41.

If I understand correctly the hardware combines an HP-IL interface and an HP-IL<->RS-232 interface which is used to talk to specific surveyors transits. The specific protocols for individual brands may be contained in separate modules.

Is it possible to use the hardware has a pure RS-232 interface rather than to talk to a transit?